1. Field of the Invention
The present invention relates to an image recording apparatus for detecting a recording material in advance before recording an image, and making a masking amendment to the image recording position based on the detection result.
2. Description of the Related Art
Recently, there is an increasing need for an image recording apparatus to record an image on the entire recording material in outputting an image such as a photo, graphics, etc. other than characters, charts, and tables.
To satisfy the above-mentioned need, it is necessary to record an image after correctly grasping the position of a recording material. To detect the correct position, a line sensor, etc. is normally used, and the image recording position is fed back to a control unit before recording an image.
However, for example, when the line sensor becomes dirty with a foreign object attached to the line sensor, the position of the recording material cannot be correctly detected, thereby recording an image to a portion other than the recording material, or losing the recording image information for image-recording to a recording material. The above-mentioned conventional image recording apparatus is disclosed by, for example, the patent document 1 (Japanese Published Patent Application No. 2000-223088).
The image recording apparatus according to the patent document 1 has a form sensor for detecting the slippage in position of a recording material including a light emitting device (LED) and a receiving optics, has the function of detecting the amount of slippage in the horizontal scanning direction of the recording material according to the signal from the receiving optics of the form sensor when an image is recorded, and masking the portion on the recording material other than the image recording area, and performs control of notifying an operator of an incorrect detection and stopping recording an image when there is an incorrectly detected position in the image recording area other than the masked area due to dirt, etc. attached to the form sensor.
However, as described in the patent document 1, the method of masking an area by detecting an image recording position on the recording material by the receiving optics of the line sensor, etc. is only to stop performing amending control of the image recording position or to notify an operator if the incorrect detection of the receiving optics is found in a necessary area for edge detection in the horizontal scanning direction of the recording material. When the amending control is not performed on the image recording position, it is necessary to reserve a large margin from the side edge (horizontal end), and there occurs a slippage in image recording position between the face and the reverse with the image recording apparatus having a double-sided recording mechanism.
Furthermore, according to the patent document 1, since the receiving optics detects only one edge on the recording material, the edges of both sides of the recording material cannot be appropriately masked.